CN113278795B - Wet smelting method for high nickel matte - Google Patents

Abstract

The invention provides a high nickel matte wet smelting method. The smelting method includes step S1 of electrolyzing the anode containing high nickel matte to obtain nickel-rich solution and anode butt; step S2 of performing oxygen pressure leaching on the anode residue to obtain nickel-containing leaching solution and leaching slag. Through the above smelting method, the anode including high nickel matte is firstly electrolyzed, so that most of the nickel in the high nickel matte enters the electrolyte. Afterwards, oxygen pressure leaching is performed on the anode anode, so that the nickel in the anode anode can further enter the liquid, and further increase the amount of nickel separated from the raw material. In the oxygen pressure leaching process, the difference in reduction potential between elements is used to reduce and replace the impurity ions with higher reduction potential in the leaching solution with nickel, so that the impurity ions remain in the leaching slag as sulfide, making nickel and sulfur and impurities The ions are effectively separated.

Description

High nickel matte hydrometallurgy method

technical field

The invention relates to the technical field of hydrometallurgy, in particular to a high nickel matte hydrometallurgy method.

Background technique

High nickel matte is a sulfide eutectic of nickel, copper, cobalt, iron and other metals obtained by primary smelting of nickel concentrate through electric and converter. Generally, it is a block containing 50-75% nickel, 1-15% copper, 0.1-1.5% cobalt, 1-5% iron, and 20-25% sulfur. Electrolytic nickel can be produced by electrolysis or high pressure Nickel sulfate is produced by leaching. Due to the recent success of Vale Indonesia’s conversion of ferronickel to high-nickel matte, high-nickel matte has become an important smelting intermediate product of laterite nickel ore and nickel sulfide ore, and has attracted much attention in the field of nickel processing.

The production process of high nickel matte at home and abroad can be summarized as follows: a. Direct electrolysis of high nickel matte anode, b. Chlorination refining process of high nickel matte, c. Reduction roasting electrolysis process of nickel concentrate, d. Normal pressure leaching process of high nickel matte, e. High pressure leaching process of nickel matte, f. High matte nickel oxidation roasting acid leaching process. Among them, the processes related to electrolysis are basically directly electrowinning to produce cathode nickel. The anode plate remaining after electrolysis needs to be processed with a suitable matching process, and the impurity removal and purification process is also relatively complicated; the electrolysis process is not perfect, and normal pressure or added The leaching rate of pressure leaching alone is not high enough. Usually, several methods are linked together to achieve better leaching effect, such as using one-stage atmospheric pressure leaching combined with electrowinning and two-stage pressure leaching to treat high nickel matte; or using electrolysis combined with one-stage atmospheric pressure acid leaching and two-stage chlorine leaching There are many processes to deal with high nickel matte, but these processes have too many processes to facilitate operation and reduce costs.

Contents of the invention

The main purpose of the present invention is to provide a high-nickel matte wet smelting method to solve the problems in the prior art that the process of electrolytically dissolving the high-nickel matte anode plate is relatively complicated and the cost is high.

In order to achieve the above object, according to one aspect of the present invention, a high-nickel matte hydro-smelting method is provided, the hydro-smelting method comprises: step S1, electrolyzing the anode including high-nickel matte to obtain nickel-rich solution and anode butt; step S2 , carry out oxygen pressure leaching to the butt anode to obtain nickel-containing leaching solution and leaching slag.

Further, the above step S1 includes: causing an electrolytic reaction to occur in the electrolysis system including the cathode, electrolyte and anode to obtain a nickel-rich solution and anode residue, the concentration of H ⁺ in the electrolyte is 1-2 mol/L, and the volume concentration of hydrogen peroxide is 1 %～10%, the concentration of copper ions is 5～15g/L, the concentration of manganese ions is 5～15g/L, preferably the electrolyte also contains sodium chloride and the concentration of sodium chloride is 50～120g/L, preferably The H ⁺ in the electrolyte is provided by sulfuric acid; preferably there are multiple anodes and cathodes, and the distance between the anode and the cathode is 10-30cm, and the anode current density is preferably 200-350A/m ² , and the electrolysis voltage is 2.8 ～4.0V, the electrolysis reaction is preferably carried out in an oxygen-containing gas, preferably the oxygen content in the oxygen-containing gas is 20-100%, the flow rate of the oxygen-containing gas is 0.05-2.5L/min, and the temperature of the electrolysis reaction is preferably 55-75 ℃.

Further, the electrolytic reaction in the above step S1 is carried out in stages, and whenever the nickel content in the nickel-rich solution reaches 40-50 g/L, the electrolytic reaction at this stage is stopped, and the electrolytic solution is added after the nickel-rich solution is separated to continue the electrolytic reaction , until anode butts are generated.

Further, the above-mentioned electrolysis system is divided into an anode reaction zone and a cathode reaction zone, the anode reaction zone includes the electrolyte and the anode, the cathode reaction zone includes the electrolyte and the cathode, and the liquid level of the electrolyte in the anode reaction zone is preferably higher than that of the cathode reaction zone. The liquid level of the liquid is 3-5cm high, preferably during the electrolysis reaction, the H ⁺ concentration in the electrolyte in the anode reaction zone is kept at 1-2mol/L, the volume concentration of hydrogen peroxide is kept at 1%-10%, and the concentration of copper ions is kept at 1-2mol/L. At 5-15g/L, the concentration of manganese ions is kept at 5-15g/L. During the electrolysis reaction, the concentration of H ⁺ in the electrolyte in the cathode reaction zone is kept at 1-2mol/L, and the volume concentration of hydrogen peroxide is kept at 1 %~10%.

Further, the above step S2 includes: crushing the anode butt and mixing it with a nickel-rich solution to obtain a dispersion liquid, preferably the weight content of particles with a particle diameter ≤ 400 mesh in the crushed anode butt is 60% to 80%; oxygenating the dispersion liquid Pressure leaching to obtain nickel-containing leachate and leaching residue, preferably the dispersion also contains hydrogen peroxide, and preferably the solid-to-liquid ratio in the dispersion is 2-10g:1L.

Further, during the above oxygen pressure leaching process, the leaching oxygen partial pressure is 0.05-0.5Mpa, the leaching temperature is 150-220°C, and the content of sulfuric acid in the leaching solution is preferably 10-20g/L at the end of the leaching.

Further, the above-mentioned smelting method also includes a recovery process of the leaching slag, preferably, the recovery process includes: oxidizing and sintering the leaching slag to obtain metal oxides.

Further, the above-mentioned smelting method also includes the process of removing impurities from the leachate. The impurity removal process includes: step A1, adjusting the pH value of the leachate to 1.5-3, preferably using metal oxides to adjust the pH value of the leachate; step A2, heating the pH value The leaching solution is 1.5-3 to obtain a nickel-rich slurry; step A3, solid-liquid separation of the nickel-rich slurry to obtain impurity precipitation and nickel-rich solution; step A4, purification of the nickel-rich solution to obtain nickel salt.

Further, in the above-mentioned step A2, the heating temperature is 70-90° C. and the heating time is 0.5-1 h, and it is preferable to maintain the pH value of the leaching solution at 1.5-3 during the heating process.

Further, the above step A4 includes: extracting the nickel-rich solution to obtain a raffinate and a nickel-containing extract, preferably the raffinate contains copper ions and manganese ions and the raffinate provides at least part of the copper ions and Manganese ions, the extractant used for extraction includes P204 extractant; the nickel-containing extract is subjected to back-extraction treatment to obtain a nickel salt solution; the nickel salt solution is subjected to crystallization treatment to obtain a nickel salt.

Applying the technical solution of the present invention, first, the anode including high nickel matte is electrolyzed, so that most of the nickel in the high nickel matte enters the electrolyte, and when the anode can no longer continue to react, a nickel-rich solution with a high nickel content is correspondingly obtained and anode butts. Afterwards, oxygen pressure leaching is performed on the anode anode, so that the nickel in the anode anode can further enter the liquid, and further increase the amount of nickel separated from the raw material. During the oxygen pressure leaching process, not only nickel enters the leaching solution, but also impurity ions such as copper, iron, cobalt, etc. also enter the leaching solution at the same time. Due to the difference in reduction potential between elements, especially the reduction potential of nickel is low, Therefore, the impurity ions with higher reduction potential in the leaching solution are reduced and replaced with nickel, so that the impurity ions remain in the leaching slag as sulfides, so that nickel, sulfur and impurity ions are effectively separated. With the smelting method of the present application, sulfur and nickel in high nickel matte can be effectively separated through two steps, which simplifies the process and effectively reduces the cost while ensuring high separation efficiency.

detailed description

It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present invention will be described in detail below in conjunction with examples.

According to the description in the background technology of this application, the process of electrolyzing high nickel matte anodes in the prior art has the problems of complicated process and high cost. In order to solve the above problems, this application provides a high nickel matte wet smelting method. The smelting method includes: step S1, electrolyzing the anode containing high nickel matte to obtain nickel-rich solution and anode butt; step S2, performing oxygen pressure leaching on the anode residue to obtain nickel-containing leaching solution and leaching slag.

Through the above smelting method, the anode including high nickel matte is first electrolyzed, so that most of the nickel in the high nickel matte enters the electrolyte solution, and when the anode can no longer continue to react, a nickel-rich solution and residual anode with a high nickel content are correspondingly obtained pole. Afterwards, oxygen pressure leaching is performed on the anode anode, so that the nickel in the anode anode can further enter the liquid, and further increase the amount of nickel separated from the raw material. During the oxygen pressure leaching process, not only nickel enters the leaching solution, but also impurity ions such as copper, iron, cobalt, etc. also enter the leaching solution at the same time. Due to the difference in reduction potential between elements, especially the reduction potential of nickel is low, Therefore, the impurity ions with higher reduction potential in the leaching solution are reduced and replaced with nickel, so that the impurity ions remain in the leaching slag as sulfides, so that nickel, sulfur and impurity ions are effectively separated. With the smelting method of the present application, sulfur and nickel in high nickel matte can be effectively separated through two steps, which simplifies the process and effectively reduces the cost while ensuring high separation efficiency.

In some embodiments, the above step S1 includes: making the electrolysis system including the cathode, the electrolyte and the anode undergo an electrolysis reaction to obtain a nickel-rich solution ^and anode residue, the concentration of H in the electrolyte is 1-2 mol/L, and the volume of hydrogen peroxide is The concentration is 1%-10%, the concentration of copper ions is 5-15g/L, and the concentration of manganese ions is 5-15g/L. By adjusting the concentration of H ⁺ and hydrogen peroxide in the electrolyte, the electrolyte has strong acidity and oxidation; and the manganese ions and copper ions in the electrolyte undergo substitution reactions with nickel ions, so that more nickel ions enter into the electrolyte, while copper and manganese form sulfide precipitates and separate from nickel in the form of anode slime, so that the high nickel matte undergoes a catalytic oxidation reaction, effectively electrolyzing the nickel in the high nickel matte from the anode into the solution. Moreover, the setting of the above numerical range can further improve the effect of nickel separation. If the concentration of manganese ions and copper ions exceeds the above range, there will be too many residual manganese ions and copper ions in the electrolyte after the electrolytic reaction. Preferably, the electrolyte also contains sodium chloride and the concentration of sodium chloride is 50-120g/L. Sodium chloride within the above concentration range can provide sufficient electrolyte for the electrolyte, so that the impedance of the electrolyte is low during the electrolysis process , and avoid the increase of the viscosity of the electrolyte caused by the excessive concentration of sodium chloride to hinder the anode electrolysis, so as to ensure that the electrolysis reaction maintains a high rate. The acid for adjusting the pH of the electrolyte in the present application can be selected from commonly used acids, such as acids such as hydrochloric acid, sulfuric acid or nitric acid, in order to avoid producing toxic gases in the reaction process, ^and to ensure the stability of the system, preferably the H in the electrolyte is formed by Sulfuric acid provided.

The setting method of the electrolysis system of the present application and the parameter setting in the electrolysis process can be designed by using methods commonly used in the art. In order to improve the smelting efficiency, it is preferred that the anode and the cathode each have multiple, and the respective homopolar center distances of the anode and the cathode The size is 10-30cm, and multiple anodes and cathodes are used for electrolysis at the same time, which increases the contact area between the anode and the electrolyte, thereby improving the electrolysis efficiency. In some embodiments, the anode current density is 200-350A/m ² , and the electrolysis voltage is 2.8-4.0V. Under the above conditions, the anode can be electrolyzed evenly and quickly, which effectively improves the efficiency of the smelting method of the present application. In order to make more nickel in the high nickel matte oxidized into the electrolyte, it is preferable to carry out the electrolysis reaction in an oxygen-containing gas, preferably the oxygen content in the oxygen-containing gas is 20-100%, and the flow rate of the oxygen-containing gas is 0.05-2.5 L/min, so that chemical catalytic oxidation is carried out on the basis of electrocatalytic oxidation at the same time, and the dissolution rate of nickel from the anode to the electrolyte is increased. If the oxygen flow rate is too low, the reaction will be slow and too large, which will cause the liquid level of the electrolytic tank to fluctuate, and the electrolytic reaction will not be carried out smoothly. The temperature of the electrolysis reaction is preferably 55-75°C. If the temperature is lower than the above range, the reaction speed is too slow. If the temperature is higher than the above range, a large amount of water in the electrolytic cell will evaporate and lose during the electrolysis process, resulting in more acid mist and pollution.

When the nickel concentration in the electrolytic solution gradually increases as the reaction progresses, the speed of the above-mentioned electrolytic reaction will gradually decrease, so the electrolytic reaction of the above-mentioned step S1 is preferably carried out in stages, whenever the nickel content in the nickel-rich solution reaches 40～50g /L, stop the electrolytic reaction at this stage, add fresh electrolyte after the nickel-rich solution is separated, and continue the electrolytic reaction until anode butts are generated. During the electrolysis process, the nickel content in the electrolyte is monitored, and when it reaches a threshold value in the range of 40-50g/L, the above-mentioned electrolysis reaction is stopped, and a new electrolyte solution is replaced to further carry out the electrolysis reaction. The replaced electrolyte is part of the nickel-rich solution. When the anode fails to react further, the anode butt mentioned above is obtained.

In order to further improve the stability of the reaction and make the reaction of the anode less disturbed, it is preferable that the electrolysis system is divided into an anode reaction zone and a cathode reaction zone. The anode reaction zone includes the electrolyte and the anode, and the cathode reaction zone includes the electrolyte and the cathode. The method of dividing the electrolyte system into an anode reaction zone and a cathode reaction zone can be selected from the prior art by those skilled in the art. Preferably, the anode and part of the electrolyte are packed into the anode bag, and the cathode and another part of the electrolyte are packed into the anode bag. Into the electrolytic cell, the anode bag is placed in the electrolytic cell to form the separation of the anode and the cathode. The electrolytic cell can be further divided into an anode chamber and a cathode chamber, the anode is bagged in the anode chamber containing the electrolyte, and the cathode is directly placed in the cathode chamber of the electrolyte to further achieve the effect of separation.

The electrolyte in the anode reaction zone and the cathode reaction zone are connected through the anode bag, preferably the liquid level of the electrolyte in the anode reaction zone is 3 to 5 cm higher than that in the cathode reaction zone, so that the electrolyte in the cathode reaction zone depends on The static pressure difference will not flow into the anode reaction zone, ensuring the stability of the reaction environment in the anode reaction zone. Preferably, during the electrolysis reaction, the concentration of H ⁺ in the electrolyte in the anode reaction zone is kept at 1-2mol/L, the volume concentration of hydrogen peroxide is kept at 1%-10%, the concentration of copper ions is kept at 5-15g/L, and the concentration of manganese ions is kept at 1-2mol/L. The concentration of hydrogen peroxide is kept at 5-15g/L. During the electrolysis reaction, the concentration of H ⁺ in the electrolyte in the cathode reaction zone is kept at 1-2mol/L, and the volume concentration of hydrogen peroxide is kept at 1%-10%, so that the reaction can be more efficient. proceed steadily.

After electrolysis, there is still part of nickel in the butt anode that has not been electrolyzed. At this time, the nickel can be further recovered through the above-mentioned oxygen pressure leaching. The above oxygen pressure leaching can be referred to the conventional oxygen pressure leaching process in the prior art. In some embodiments of the present application, the above step S2 includes: crushing the residual anode and mixing it with a nickel-rich solution to obtain a dispersion, preferably broken residual anode The weight content of particles with a particle size of ≤400 mesh in the pole is 60% to 80%; oxygen pressure leaching is carried out on the dispersion liquid to obtain nickel-containing leachate and leaching slag. Since the nickel-enriched solution of the present application has a high acidity and contains More copper ions and manganese ions. On the one hand, the copper ions and manganese ions in the nickel-rich solution can be used as reducing agents to leach more nickel; on the other hand, once the nickel in the butt anode is leached, the sulfur in it will also enter the leaching solution. At this time, the copper ions in the nickel-rich solution can be used as a sulfur-fixing agent to form copper sulfide, so that sulfur remains in the leaching slag. It is preferable that hydrogen peroxide is further included in the dispersion liquid, and the solid-to-liquid ratio in the dispersion liquid is preferably 2-10 g:1L. The nickel in the butt anode is further leached by mixing the finely divided anode butt with the nickel-rich solution, and further adding hydrogen peroxide to increase the concentration of the oxidant.

In order to further improve the separation effect of the above-mentioned oxygen pressure leaching on nickel, preferably in the above-mentioned oxygen pressure leaching process, the leaching oxygen partial pressure is 0.05-0.5Mpa, and the leaching temperature is 150-220°C. The acid content is relatively high. As the oxygen pressure leaching proceeds, the hydrogen ions in the leaching system are consumed. It is preferable that the content of sulfuric acid in the leaching solution be 10-20g/L at the end of the leaching to ensure the full leaching of nickel and avoid excessive leaching. Impurity ion leaching.

In some embodiments, the above smelting method further includes a process of recovering the leaching slag, preferably, the recovery process includes: oxidizing and sintering the leaching slag to obtain metal oxides. By oxidizing and sintering the leaching slag, the leaching slag is desulfurized to obtain metal oxides.

The leach solution obtained by the above-mentioned oxygen pressure leaching contains a certain amount of impurity metal ions. In order to finally obtain nickel salt with less impurities, the above-mentioned smelting method preferably also includes a process of removing impurities from the leach solution. The impurity removal process includes: step A1, adjusting The pH value of the leaching solution is 1.5-3; step A2, heating the leaching solution with a pH value of 1.5-3 to obtain a nickel-rich slurry; step A3, performing solid-liquid separation on the nickel-rich slurry to obtain impurity precipitation and nickel-rich solution; step A4, Purify the nickel-rich solution to obtain nickel salt. As mentioned above, the leaching solution of the present application contains a lot of residual acid. By adding alkaline reagents to adjust the pH value of the leaching solution and performing heat treatment, impurity metal ions such as iron can enter the precipitation residue and be removed. Preferably, the above-mentioned metal oxides are used to adjust the pH value of the leaching solution, so that the residual nickel in the metal oxide obtained by oxidizing and sintering the leaching slag further enters the leaching solution, thereby increasing the recovery rate of nickel.

In order to improve the effect and efficiency of precipitation and separation of impurity metals such as iron, it is preferred that in the above step A2, the heating temperature is 70-90° C. and the heating time is 0.5-1 h. Preferably, the pH of the leaching solution is maintained at 1.5-3 during the heating process. The pH value of the leachate during the heating process can be maintained by using an alkaline reagent for production. In order to avoid introducing impurities that are difficult to separate, it is preferred to use one or both of sodium carbonate and sodium bicarbonate to adjust the above pH.

In some embodiments, it is preferable that the above-mentioned step A4 includes: extracting the nickel-rich solution to obtain a raffinate and a nickel-containing extract, and the extraction agent used in the extraction includes a P204 extractant; performing back-extraction treatment on the nickel-containing extract, A nickel salt solution is obtained; the nickel salt solution is crystallized to obtain a nickel salt. Nickel salt is obtained by the above-mentioned extraction and crystallization treatment. When sulfuric acid is used to adjust the pH in the electrolytic reaction, the above-mentioned nickel salt is nickel sulfate. The nickel salt obtained by using the smelting method of the present application has high purity and can be used in the field of new energy. In order to further improve the recycling rate of the catalyst in the smelting method of the present application, it is preferable that the raffinate contains copper ions and manganese ions and the raffinate provides at least part of the copper ions and manganese ions for the electrolyte.

Below in conjunction with embodiment and comparative example, further illustrate the beneficial effect of the present application.

Example 1

1) High-nickel matte anode melting and casting: High-nickel matte is melted and cast into a high-nickel matte anode of 8cm*10cm, and a titanium plate of 10*12cm is selected as the cathode for electrolytic dissolution.

2) Electrolysis: the anode is bagged, and the electrolyte is prepared (which contains 70g/L sodium chloride, 100g/L sulfuric acid, hydrogen peroxide with a volume concentration of 2%, copper ions 5g/L copper ions and 7g/L manganese ions). The electrolytic cell is filled with this electrolyte, and a plurality of anode bags and cathodes are placed in the electrolytic cell, wherein the center-to-center distance of the same pole is 20 cm, and the liquid level in the anode bag is 3 cm higher than the liquid level of the electrolytic cell. Use the above electrolysis system to carry out electrolysis reaction, control the anode current density of 230A/m ² , the cell voltage of 3.0V, the temperature in the electrolytic cell at 60°C, keep 0.1L/min of oxygen in the anode bag, and the electrolytic cell is in the process of electrolysis Stirring was continued (stirring speed was 10 rpm) to keep the electrolyte homogeneous during the reaction. During the electrolysis process, the electrolytic solution is drawn out, and an appropriate amount of sulfuric acid, hydrochloric acid and hydrogen peroxide is added to it, and the part of the electrolytic solution is returned to the electrolytic cell, so that the concentration of hydrogen ions, chloride ions and hydrogen peroxide in the electrolytic cell is reduced during the reaction process. Basically remain unchanged. Then the electrolyte (which contains 70g/L sodium chloride, 100g/L sulfuric acid, hydrogen peroxide with a volume concentration of 2%, copper ions 5g/L copper ions and 7g/L manganese ions) is continuously injected into the anode bag to keep the anode bag While the difference between the liquid level and the cathode liquid level is maintained at 3 cm, the concentrations of chloride ions, hydrogen ions, copper ions, manganese ions and hydrogen peroxide in the anode bag remain constant. When the nickel content in the solution in the electrolytic cell reaches 50g/L, the electrolysis is stopped, and the solution is extracted to obtain a part of the nickel-rich solution. Add new electrolytic solution to continue the above electrolytic reaction until the anode becomes a butted anode, and mix the withdrawn electrolytic solution with a nickel content of 50 g/L to obtain a nickel-rich solution.

3) Electrolytic anode residue crushing: take out the anode residue, wash it with water, and crush it by ball milling, so that the final particle size of the broken anode residue below 400 mesh reaches 70%.

4) Pressure leaching: Mix and crush the broken anode, nickel-rich solution and hydrogen peroxide so that the solid-liquid ratio reaches 5g:1L. Under the conditions of 150°C and 0.1Mpa oxygen partial pressure, oxygen pressure leaching is performed for 2 hours to obtain leaching solution and leaching residue. The concentration of sulfuric acid in the leaching solution is 10g/L.

5) Desulfurization of the leaching slag: After drying the leaching slag, put it into a furnace to raise the temperature to 950°C, and oxidize and roast it for 2 hours with air (flow rate: 1L/min) to obtain metal oxides.

6) Impurity removal: add the metal oxide obtained in step 5) to the leaching solution to adjust the pH value to 2, heat to 80°C for 0.5h, and continuously add 10g/L sodium carbonate solution to maintain the pH value of the system at 2, and obtain rich Nickel slurry, iron-containing slag and nickel-rich solution are obtained after solid-liquid separation.

7) Using the P204 extractant to extract the nickel-rich solution, after back extraction and crystallization treatment, nickel sulfate crystals are obtained, and the leaching rate of nickel is 98.5%.

Example 2

1) High-nickel matte anode melting and casting: High-nickel matte is melted and cast into a high-nickel matte anode of 8cm*10cm, and a titanium plate of 10*12cm is selected as the cathode for electrolytic dissolution.

2) Electrolysis: the anode is bagged, and the electrolyte is prepared (which contains 90g/L sodium chloride, 140g/L sulfuric acid, hydrogen peroxide with a volume concentration of 4%, copper ions 10g/L copper ions and 12g/L manganese ions). The electrolytic cell is filled with this electrolyte, and a plurality of anode bags and cathodes are placed in the electrolytic cell, wherein the center distance of the same pole is 20 cm, and the liquid level in the anode bag is 4 cm higher than the liquid level of the electrolytic cell. Use the above electrolysis system to carry out the electrolysis reaction, control the anode current density to 300A/m ² , the cell voltage to 3.5V, the temperature in the electrolytic cell to be 65°C, keep 0.2L/min of oxygen in the anode bag, and the electrolytic cell is in the process of electrolysis Stirring was continued (stirring speed was 10 rpm) to keep the electrolyte homogeneous during the reaction. During the electrolysis process, the electrolytic solution is drawn out, and an appropriate amount of sulfuric acid, hydrochloric acid and hydrogen peroxide is added to it, and the part of the electrolytic solution is returned to the electrolytic cell, so that the concentration of hydrogen ions, chloride ions and hydrogen peroxide in the electrolytic cell is reduced during the reaction process. Basically remain unchanged. Then the electrolyte (which contains 70g/L sodium chloride, 100g/L sulfuric acid, hydrogen peroxide with a volume concentration of 2%, copper ions 5g/L copper ions and 7g/L manganese ions) is continuously injected into the anode bag to keep the anode bag While the difference between the liquid level and the cathode liquid level is maintained at 4cm, the concentrations of chloride ions, hydrogen ions, copper ions, manganese ions and hydrogen peroxide in the anode bag remain constant. When the nickel content in the solution in the electrolytic cell reaches 45g/L, the electrolysis is stopped, and the solution is extracted to obtain a part of the nickel-rich solution. Add new electrolytic solution to continue the above electrolytic reaction until the anode becomes a butted anode, and mix the withdrawn electrolytic solution with a nickel content of 45 g/L to obtain a nickel-rich solution.

3) Electrolytic anode residue crushing: take out the anode residue, wash it with water, and crush it by ball milling, so that the final particle size of the broken anode residue below 400 mesh reaches 70%.

4) Pressure leaching: Mix and crush the broken anode, nickel-rich solution and hydrogen peroxide so that the solid-liquid ratio reaches 6g:1L. Under the conditions of 180°C and 0.2Mpa oxygen partial pressure, oxygen pressure leaching is carried out for 3 hours to obtain leaching solution and leaching residue. The concentration of sulfuric acid in the leaching solution is 15g/L.

5) Desulfurization of the leaching slag: After drying the leaching slag, put it into a furnace to raise the temperature to 950°C, pass air (flow rate: 1L/min) and oxidize and roast for 1 hour to obtain metal oxides.

6) Impurity removal: add the metal oxide obtained in step 5) to the leaching solution to adjust the pH value to 2.2, heat to 80°C for 0.5h, and continue to add 10g/L sodium carbonate solution to maintain the pH value of the system at 2.2 to obtain rich Nickel slurry, iron-containing slag and nickel-rich solution are obtained after solid-liquid separation.

7) Using P204 extractant to extract the nickel-rich solution, after back extraction and crystallization treatment, nickel sulfate crystals are obtained, and the leaching rate of nickel is 99.2%. The copper ions and manganese ions in the raffinate are recycled to the electrolyte solution in step 2).

Example 3

1) High-nickel matte anode melting and casting: High-nickel matte is melted and cast into a high-nickel matte anode of 8cm*10cm, and a titanium plate of 10*12cm is selected as the cathode for electrolytic dissolution.

2) Electrolysis: the anode is bagged, and the electrolyte is prepared (which contains 100g/L sodium chloride, 170g/L sulfuric acid, hydrogen peroxide with a volume concentration of 6%, copper ions 15g/L copper ions and 15g/L manganese ions). The electrolyzer is filled with this electrolyte, and a plurality of anode bags and cathodes are placed in the electrolyzer, wherein the center distance of the same pole is 20cm, and the liquid level in the anode bag is 5cm higher than the liquid level of the electrolyzer. Use the above electrolysis system to carry out the electrolysis reaction, control the anode current density to 350A/m ² , the cell voltage to 4V, the temperature in the electrolytic cell to be 70°C, keep 0.35L/min of oxygen in the anode bag, and the electrolytic cell will continue to flow during the electrolysis process. Stirring (stirring speed is 10rpm) to keep the homogeneity of the electrolyte during the reaction. During the electrolysis process, the electrolytic solution is drawn out, and an appropriate amount of sulfuric acid, hydrochloric acid and hydrogen peroxide is added to it, and the part of the electrolytic solution is returned to the electrolytic cell, so that the concentration of hydrogen ions, chloride ions and hydrogen peroxide in the electrolytic cell is reduced during the reaction process. Basically remain unchanged. Then the electrolyte (which contains 70g/L sodium chloride, 100g/L sulfuric acid, hydrogen peroxide with a volume concentration of 2%, copper ions 5g/L copper ions and 7g/L manganese ions) is continuously injected into the anode bag to keep the anode bag While the difference between the liquid level and the cathode liquid level is maintained at 5cm, the concentrations of chloride ions, hydrogen ions, copper ions, manganese ions and hydrogen peroxide in the anode bag remain constant. When the nickel content in the solution in the electrolytic cell reaches 40g/L, the electrolysis is stopped, and the solution is extracted to obtain a part of the nickel-rich solution. Add new electrolytic solution to continue the above electrolytic reaction until the anode becomes a butted anode, and mix the withdrawn electrolytic solution with a nickel content of 40 g/L to obtain a nickel-rich solution.

3) Electrolytic anode residue crushing: take out the anode residue, wash it with water, and crush it by ball milling, so that the final particle size of the broken anode residue below 400 mesh reaches 80%.

4) Pressure leaching: Mix and crush the broken anode, nickel-rich solution and hydrogen peroxide so that the solid-liquid ratio reaches 8g:1L. Under the conditions of 200°C and 0.4Mpa oxygen partial pressure, oxygen pressure leaching for 5h to obtain leachate and leaching residue. The concentration of sulfuric acid in the leaching solution is 20g/L.

5) Desulfurization of the leaching slag: After drying the leaching slag, put it into a furnace to raise the temperature to 950°C, pass air (flow rate: 1L/min) and oxidize and roast for 3 hours to obtain metal oxides.

6) Impurity removal: add the metal oxide obtained in step 5) to the leaching solution to adjust the pH value to 1.8, heat to 80°C for 1 hour, and continue to add 10g/L sodium carbonate solution to maintain the pH value of the system at 1.8 to obtain nickel-rich Slurry, iron-containing slag and nickel-rich liquid are obtained after solid-liquid separation.

7) Using the P204 extractant to extract the nickel-rich solution, after back extraction and crystallization treatment, nickel sulfate crystals are obtained, and the leaching rate of nickel is 99.8%. The copper ions and manganese ions in the raffinate are recycled to the electrolyte solution in step 2).

Example 4

The difference from Example 1 is that the temperature in the electrolytic cell in step 2) is 55°C.

Example 5

The difference from Example 1 is that the temperature in the electrolytic cell in step 2) is 75°C.

Example 6

The difference from Example 1 is that the temperature in the electrolytic cell in step 2) is 45°C.

Example 7

The difference from Example 1 is that the temperature in the electrolytic cell in step 2) is 90°C.

Example 8

The difference from Example 1 is that the flow rate of oxygen in step 2) is 0.05L/min.

Example 9

The difference from Example 1 is that the flow rate of oxygen in step 2) is 2.5 L/min.

Example 10

The difference from Example 1 is that the flow rate of oxygen in step 2) is 0.02L/min.

Example 11

The difference from Example 1 is that the flow rate of oxygen in step 2) is 3.0 L/min.

Example 12

The difference from Example 1 is that the concentration of manganese ions in step 2) is 5g/L.

Example 13

The difference from Example 1 is that the concentration of manganese ions in step 2) is 15g/L.

Example 14

The difference from Example 1 is that the concentration of manganese ions in step 2) is 2g/L.

Example 15

The difference from Example 1 is that the concentration of manganese ions in step 2) is 18g/L.

Example 16

The difference from Example 1 is that the oxygen partial pressure in step 4) is 0.05Mpa.

Example 17

The difference from Example 1 is that the oxygen partial pressure in step 4) is 0.5Mpa.

Example 18

The difference from Example 1 is that the oxygen partial pressure in step 4) is 0.02Mpa.

Example 19

The difference from Example 1 is that the oxygen partial pressure in step 4) is 0.6Mpa.

Example 20

The difference from Example 1 is that the leaching temperature in step 4) is 220°C.

Example 21

The difference from Example 1 is that the leaching temperature in step 4) is 120°C.

Example 22

The difference from Example 1 is that the leaching temperature in step 4) is 250°C.

Example 23

The difference from Example 1 is that the solid-to-liquid ratio in step 4) is 2g:1L.

Example 24

The difference with Example 1 is that the solid-to-liquid ratio in step 4) is 10g:1L.

Example 25

The difference with Example 1 is that the solid-to-liquid ratio in step 4) is 1g:1L.

Example 26

The difference from Example 1 is that the solid-to-liquid ratio in step 4) is 15g:1L.

Example 27

The difference from Example 1 is that in step 6), the reaction is carried out by heating to 70°C.

Example 28

The difference from Example 1 is that in step 6), the reaction is carried out by heating to 90°C.

Example 29

The difference from Example 1 is that in step 6), the reaction is carried out by heating to 60°C.

Example 30

The difference from Example 1 is that in step 6), the reaction is carried out by heating to 95°C.

Example 31

The difference from Example 1 is that in step 4), the broken anode is mixed with hydrogen peroxide containing 100g/L sodium chloride, 170g/L sulfuric acid, and a volume concentration of 6%, copper ions 15g/L copper ions and 15g/L manganese The solution of ions is mixed, under the conditions of 200°C and 0.4Mpa oxygen partial pressure, oxygen pressure leaching for 5h, to obtain leaching solution and leaching residue. The concentration of sulfuric acid in the leaching solution is 20g/L.

The nickel leaching rate among the above-mentioned each embodiment is as shown in table 1.

Table 1

From the above description, it can be seen that the above-mentioned embodiments of the present invention have achieved the following technical effects:

Through the smelting method of the present application, first, the anode including high nickel matte is electrolyzed, so that most of the nickel in the high nickel matte enters the electrolyte solution, and when the anode can no longer continue to react, a nickel-rich solution with a high nickel content is correspondingly obtained and anode butts. Afterwards, oxygen pressure leaching is performed on the anode anode, so that the nickel in the anode anode can further enter the liquid, and further increase the amount of nickel separated from the raw material. During the oxygen pressure leaching process, not only nickel enters the leaching solution, but also impurity ions such as copper, iron, cobalt, etc. also enter the leaching solution at the same time. Due to the difference in reduction potential between elements, especially the reduction potential of nickel is low, Therefore, the impurity ions with higher reduction potential in the leaching solution are reduced and replaced with nickel, so that the impurity ions remain in the leaching slag as sulfides, so that nickel, sulfur and impurity ions are effectively separated. With the smelting method of the present application, sulfur and nickel in high nickel matte can be effectively separated through two steps, which simplifies the process and effectively reduces the cost while ensuring high separation efficiency.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (12)

1. The high nickel matte hydrometallurgy method is characterized by comprising the following steps:

step S1, electrolyzing the anode containing the high nickel matte to obtain a nickel-rich solution and a residual anode;

s2, carrying out oxygen pressure leaching on the anode scrap to obtain nickel-containing leachate and leaching residues;

in the oxygen pressure leaching process, the leaching oxygen partial pressure is 0.05 to 0.5Mpa, and the leaching temperature is 150 to 220 ℃; the step S2 includes: crushing the residual anode, and mixing the crushed residual anode with the nickel-rich solution to obtain a dispersion liquid, wherein the weight content of particles with the particle size of less than or equal to 400 meshes in the crushed residual anode is 60-80%; carrying out oxygen pressure leaching on the dispersion liquid to obtain leaching liquid containing nickel and leaching slag, wherein the dispersion liquid also contains hydrogen peroxide, and the solid-to-liquid ratio in the dispersion liquid is (2) - (10g);

the step S1 includes:

subjecting an electrolysis system comprising a cathode, an electrolyte and the anode to the electrolysis reaction to obtain the nickel-rich solution and the residual anode, wherein H is in the electrolyte ⁺ The electrolyte comprises 1 to 2mol/L of hydrogen peroxide, 1 to 10 percent of volume concentration of hydrogen peroxide, 5 to 15g/L of copper ions, 5 to 15g/L of manganese ions, sodium chloride and H, wherein the concentration of the sodium chloride in the electrolyte is 50 to 120g/L, and the volume concentration of the hydrogen peroxide in the electrolyte is 1 to 2mol/L ⁺ Provided by sulfuric acid;

the number of the anodes and the number of the cathodes are multiple, the homopolar center distance of each anode and each cathode is 10 to 30cm, and the current of each anode is denseThe degree is 200 to 350A/m ² And the electrolytic voltage is 2.8 to 4.0V, the electrolytic reaction is carried out in oxygen-containing gas, the content of oxygen in the oxygen-containing gas is 20 to 100 percent, the flow rate of the oxygen-containing gas is 0.05 to 2.5L/min, and the temperature of the electrolytic reaction is 55 to 75 ℃.

2. The nickel matte hydrometallurgical method according to claim 1, wherein the electrolytic reaction in step S1 is performed in stages, the electrolytic reaction in this stage is stopped every time the nickel content in the nickel-rich solution reaches 40 to 50g/L, the nickel-rich solution is separated, and then the electrolyte is added to continue the electrolytic reaction until the anode scrap is generated.

3. The high nickel matte hydrometallurgical method of claim 1, wherein the electrolysis system is divided into an anode reaction zone and a cathode reaction zone, the anode reaction zone comprising the electrolyte and the anode, and the cathode reaction zone comprising the electrolyte and the cathode.

4. The hydrometallurgical method for nickel matte according to claim 3, wherein the liquid level of the electrolyte in the anode reaction zone is 3 to 5cm higher than that in the cathode reaction zone.

5. The hydrometallurgical process for high nickel matte according to claim 4, wherein during the electrolytic reaction, H in the electrolyte of the anodic reaction zone is present ⁺ The concentration is kept between 1 and 2mol/L, the volume concentration of hydrogen peroxide is kept between 1 and 10 percent, the concentration of copper ions is kept between 5 and 15g/L, and the concentration of manganese ions is kept between 5 and 15g/L; h in the electrolyte in the cathode reaction zone in the electrolytic reaction process ⁺ The concentration is kept between 1 and 2mol/L, and the volume concentration of hydrogen peroxide is kept between 1 and 10 percent.

6. The nickel freematte hydrometallurgy method according to claim 1, wherein the content of sulfuric acid in the leachate is 10-20 g/L at the end of leaching.

7. The high nickel matte hydrometallurgical method according to claim 1, wherein the smelting method further comprises a recycling process of the leached slag, the recycling process comprising: and oxidizing and sintering the leaching slag to obtain the metal oxide.

8. The nickel-high matte hydrometallurgical method according to claim 7, wherein the smelting method further comprises a process of impurity removal of the leachate, the impurity removal process comprising:

step A1, adjusting the pH value of the leachate to 1.5 to 3;

step A2, heating the leachate with the pH value of 1.5 to 3 to obtain nickel-rich slurry;

step A3, carrying out solid-liquid separation on the nickel-rich slurry to obtain impurity precipitates and a nickel-rich liquid;

and A4, purifying the nickel-rich liquid to obtain nickel salt.

9. The nickel matte blast process according to claim 8, wherein the metal oxide is used to adjust the pH of the leachate.

10. The nickel matte hydrometallurgy method according to claim 8, wherein in the step A2, the heating temperature is 70 to 90 ℃ and the heating time is 0.5 to 1h.

11. The nickel matte hydrometallurgy method according to claim 10, wherein the pH of the leachate is maintained at 1.5 to 3 during the heating process.

12. The high nickel matte hydrometallurgical method of claim 8, wherein step A4 comprises:

extracting the nickel-rich liquid to obtain raffinate and nickel-containing extract, wherein the raffinate contains copper ions and manganese ions and provides at least part of the copper ions and the manganese ions for the electrolyte, and an extracting agent adopted by the extraction comprises a P204 extracting agent;

carrying out back extraction treatment on the nickel-containing extraction liquid to obtain a nickel salt solution;

and crystallizing the nickel salt solution to obtain the nickel salt.